title: Surface morphology, optical properties and conductivity changes of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) by using additives.
abstract: The optical properties and electrical conductivity of highly conducting poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) are reported as a function of the processing additive conditions. The addition of dimethyl sulfoxide (DMSO) increases the conductivity and modifies the dielectric response as observed from the ellipsometric studies. Also the surface roughness and morphology change with the composition of PEDOT:PSS:DMSO and film deposition conditions. The real part of the dielectric function becomes negative in highly conducting samples, indicating the presence of delocalized charge carriers. The real and imaginary parts of the refractive index were determined as a function of wavelength. The results are consistent with the increase in conductivity upon the addition of DMSO.
authors.affiliation: Linz Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University of Linz, Austria.
authors.forename: Jacek
authors.initials: J
authors.lastname: Gasiorowski
authors.forename: Reghu
authors.initials: R
authors.lastname: Menon
authors.forename: Kurt
authors.initials: K
authors.lastname: Hingerl
authors.forename: Marko
authors.initials: M
authors.lastname: Dachev
authors.forename: Niyazi Serdar
authors.initials: NS
authors.lastname: Sariciftci
keywords: Conducting polymers; Conductivity; Optical properties; Organic electronics; Spectroscopic ellipsometry; Surface morphology